I still believe there's a lot of potential in attributes, if only implemented properly.
First have a look at how properties and traits are completely unified with object attributes and roles/mixins in Perl 6, which pretty much covers all of your points without thinking of attributes as a separate facility. I have this crazy notion that "implemented properly" must be preceded by "designed properly", you see... :-)

In reply to Re^2: what would you like to see in perl5.12? (attributes) by TimToady
in thread what would you like to see in perl5.12? by ysth

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